Coil body for electrical apparatus



- Sept. 21 ,1926;

ELBAU I 0011. BODY ron ELECTRICAL ABPAaA'rus med Opt. s, 1924 Z I lnvenlr Patented Se t. 21, 1926.

UNITED STATES PATENT OFFICE.

EDWIN BAUER, 0] ZUG, SWITZERLAND, ASSIGNOR TO LAD'DIS it GYB A.-G., OI ZUG, SWITZERLAND (A SWISS FIRM).

COIL BODY FOR ELECTRICAL APPARATUS.

Application filed October 6, 1824, Serial No. 742,054, and in Switzerland October 9, 1823;

With the known types of spools, particularly with those which are employed in electrical apparatus, it is difficult to securely attach the inner end of the winding to the spool and it has been necessary to resort to unsatisfactory makeshifts in order to fasten this end of the winding and at the same time to avoid damaging the end of the coil which is left free for connecting up.

The object of the present invention is to eliminate the aforementioned disadvantages.

The invention relates to a spool for electrical apparatus, in whose core is a oove by means of which the end of the winding can be securely fixed and smooth winding can be obtained.

The drawing shows one arrangement for carrying out the invention.

Fig. 1 shows the spool in elevation,

Fig. 2 gives a section of the spool along the line AA in Fig. 1,

Fig. 3 shows a section along the line BB in- Fig. 1.

The spool, which may be made of mould ing material, has a core 1 and two flanges 2, 2'. The core, the outer surface of which is circular, has a central rectangular opening. Owing to this arrangement, the thickness of the wall of the core is a maximum at four sections, and atone of these sections a groove 5 is provided, running parallel to the longitudinal axis of the spool. This groove extends as far as the flange 2' and a hole is provided in the latter on a level with the bottom of the groove. Near to the fian e 2, the edge formed by the intersection of the cylindrical surface of the' core and one wall of the groove is rounded off as shown at 7. In the groove, at the end nearest to the flange 2, is a rojection, which does not, however, rise flusli with the outer surface 4 of the core.

The wire with which the coil is wound can be brought into the groove 5, and led around the pro ection 8, the inner end of the coil thus being securely attached to the spool. With this arrangement the wire used for the coil would project at one end through the hole 6, and at the othenend would be led over the rounded surface 7 on to the surany other suitable su in the manner described and the actual wire used for the coil is attached to it. After the end of the coil has been firmly attached to the spool, the goove is preferably covered by a strip 9 of insulating material fitted into it, and the winding can then be begun.

The spool need not necessarily be of circular cross section. It might, for example, be oval or approximately angular.

The spool to which the present invention relates can be employed in all kinds of electrical apparatus and can be made of any suitable material. As has already been mentioned, it might be. made of moulding material, but it could eqgatlly well be made of ance. It could, for instance, be turned from wood, in which case the groove would be milled out. What I wish to secure by Letters Patent 15:

1. A,spool for an electro-magnet or the like, comprising a core and flanges on the end thereof, said core being provided' in its face with a lon itudinal groove extending to one of the anges, for the reception of a doubled wire, a projection in said groove near its inner end to lie between the leads of the doubled wire and an openin through the flange at the outer end of said groove for the passage of one lead of the mm.

2. A spool for an electro-magnet or the like, comprising a core and flanges on the end thereof, said core being provided inits face with a longitudinal groove extending to one of the flanges, for the reception of a doubled wire, a projection in said groove near its inner end to lie between the leads,

EDWIN BA R. 

